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There are scores of Jeep JK Wrangler forums, and why not? Chrysler/Jeep just announced the build of the one-millionth JK Wrangler, and that's something to boast about!

I fielded the Camp Jeep Mopar Tent workshop questions for over a decade, and when the TJ transitioned to the new JK Wrangler platform, it was immediately clear that the new Wrangler had a more robust and stiffer frame. The suspension tuning level, NVH advancements and sound deadening were unfounded in earlier Jeep utility models—yet the iconic ladder frame and beam axles were still in place...

This vehicle went on to steal the SUV market with its popular Unlimited four-door option. The Rubicon Edition enjoys an industry-wide reputation. When I tested the 2012 model with the Pentastar 3.6L V-6 replacement for the 3.8L V-6, the new A580 five-speed automatic transmission got my attention. I tested and personally picked the 2012 Jeep JK Wrangler Unlimited Rubicon 4x4 as the magazine's "Best SUV of the Year!"

Note: If you're curious about the JK Wrangler coverage and perspective at the magazine, type 'JK Wrangler' into the keyword list at the magazine's search box.

When the economic debacle hit, the days of the Suburban and Excursion were already done. The Jeep JK Wrangler quickly filled a consumer void, and the idea of having a good time, not just getting from point 'A' to point 'B', captured the imagination of new buyers.

Our fresh forums hold the promise of reaching 4x4 enthusiasts at a new level. In the case of JK Wrangler owners, this means everyone from the Rubicon Trail runners who really do need 37" diameter tires to suburban families trying to maintain a vehicle and feed a family at the same time.

Wondering just what kind of information you can find here? Join and post your topics! Expect objective, "real" replies that won't have you asking your bank for an extended line of credit to buy "must have" modifications and upgrades. Sure, there's a place for upgrades, and I'd be pleased to point out when and why.

Expect candid answers to questions like which model Jeep JK Wrangler to buy in the first place or what you really need to reach your planned destinations.

There's no agenda at this forum. The goal is simply safe, fun use of your 4x4 JK Wrangler. Whether maximizing fuel economy is your aim, restoring or replacing powertrain components, or prepping for the ultimate destination four-wheeling, get your facts straight—here!

We welcome your forum membership and participation...

Moses

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I have a 2013 Jeep JK Wrangler Rubicon Unlimited. I off-road it quite a bit. It is lifted 4" all suspension including shock mounting, sway bars etc have been replaced/ re-worked, it is running on 37" tires, new driveshaft etc. I am running into the well documented issue of the water pump beginning to squeak and squeal. I am interested in swapping the stock pump out for a digital thermally controlled electric 115 LPM water pump from Davies Craig.

Two questions: is this a reasonable alternative to replacing the stock pump for a daily driven off road vehicle, and how do I go about re-routing the serpentine belt?

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Welcome to the forums, nbruno! I am at Moab EJS (not at my shop/studio) and would like to explore the Davies Craig water pump further. I took a quick look at the corporate site, and the electric water pump is interesting. I would like to research the longevity (duty cycle) of the electric motor when running continuously or thermally activated. It would run continuously in a warmed-up engine in all likelihood, and engine coolant heat is substantial.

Also, re-routing the belt to stop turning a squeaky mechanical pump is suspect. The parked impeller could create a blockage of flow. I would like to know the problem with the OEM water pump. Is anyone making an OE mechanical water pump that does not create trouble? On that note, is the problem squeaks or actual bearing and eventual seal failure? Squeaking can sometimes be strictly belt and pulley related.

Please share what you know. I'm glad to research further so we can determine a sensible remedy...

Moses

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The re-routing of the belt would be necessary if I install the electric water pump as there would no longer be a pulley at that location. As for OE mechanical pumps, only Mopar makes them at this point for the 3.6L Pentastar. I am unsure if the issue is actual bearing related, several guys in my jeep club have brought theirs in with the squeaking and the dealer replaced it. It is a known issue with this motor.

My question is can this be avoided in the future by switching to an electrical water pump, and would this be a superior option to the belt driven mechanical pump? And, is it worth the effort to undertake this modification as opposed to replacing it with the OE pump.

Thanks again.

Nate

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The usual argument for removing engine driven devices would be an increase in available power. One example would be the power saving water pump that doubles as the alternator for NASCAR vehicles. (Note that a NASCAR vehicle does not have a laundry list of electric power options, and the lighter output alternator merely powers up the electronics, gauges, chassis and engine support devices.) It's not surprising, though, that some would target the mechanical water pump as a parasitic, power robbing device.

Let's look at this realistically. Most 3.6L Pentastar engines drive an air conditioning compressor, power steering pump, high output alternator and such, each impacting performance to one degree or another. The engine driven water pump is a critical component with a vital function. In most conventional RWD engine applications, the water pump drives a fan and fan clutch. The actual horsepower loss from driving the water pump is lessened by the use of the fan clutch, a device that has been around since the 1960s.

Consider the power drain versus the engine's dependency on the mechanical water pump. An electric water pump would demand more alternator draw, which is a horsepower loss, depending upon the amperage draw. (There is a great example of alternator load in the use of an onboard frequency welder like a Premier Welder. Without a hand throttle, you would easily stall the engine under welding loads.) Not sure what the amperage draw might be on a water pump with the capacity to meet a Pentastar 3.6L engine's gallon-per-minute coolant flow demand under load. This could be determined, though.

Let's also consider that an electric water pump is much different than an electric fan system. The electric fan system simply needs to draw enough CFM air flow through a radiator core, it's the radiator's job to dissipate heat and actually cool the engine. A water pump, on the other hand, must run continuously to handle the cooling demands of an IC engine. The liquid cooled IC engine has natural hot spots, and the only way to prevent steam pockets and overheating in these hot areas is to constantly circulate the coolant. During engine warm-up (brief and still allowing some coolant movement), conventional cooling systems might have somewhat less dependency on the mechanical water pump...It's one thing to be dependent on an electric fan, as most engines can stay cool without any fan once vehicle speed reaches 30-40 mph or so.

All of this said, and considering the necessary modifications, I personally would not convert a 3.6L Pentastar engine to electric water pump cooling. Unless a company can produce a "kit" that makes this an easy install (including the water pump cavity and coolant distribution adapters, the hoses, mounting brackets, wiring harness, etc.), with backup research showing noticeable gains in power, performance and fuel efficiency, and engine longevity, I don't see much future for electric water pump conversions to fit the JK Wrangler Pentastar engines.

I could, however, see an aftermarket water pump manufacturer jumping into this 3.6L V-6 water pump failure issue that you share. If Mopar can't produce a quality pump, others may be able to redesign and improve the 3.6L pump to last. OE pumps like the 4.0L pump often last for 150-200K miles with a serpentine belt drive system. 100-150K miles would certainly be a reasonable target for mechanical pump life.

I'd welcome additional facts, arguments and discussion, either for or against the use of an electric water pump...The fan clutch made a dramatic difference in reducing engine load and helping to prevent radiator air blockage at higher road and engine speeds. Let's look for similarly overwhelming reasons to install an electric water pump.

As a further concern and consideration, the water pump has a big job to do—under continuous heat and load...How long will it last? Will it survive on the Rubicon Trail under load at a crawl pace, or will the electric water pump require its own cooling system?